Automatic vehicle controlling system



April 29. 1924.

E. c. SA'SNETT AUTOMATIC VEHICLE CONTROLLING SYSTEM Fil ed April 4, 1923 5|" neuter I Patented Apr. 29, 1924.

U ITED srA'res' -1,492,1'sz PATENT OFFICE.

To all whom it mag concern: v Be it known that I, Enwsnn C. Sasxm,

a citizen of the United States, and a resident of Washingto useful Improvements in Automatic Vehicle Controlling S stems, of which the followi is a speci cation.

- the y invention relates to automatic vehicle controlling systems and more particularlg to systems for controlling rai way vehic as in accordance with traflic conditions. It has for its general ob'ect to provide a s stem b means of whic c e may automatically controlled under caution and danger conditions. A specific object of the invention is to produce a stem by means of which the speed of a ve icle must necessarily be reduced under caution conditions n accordance with a predetermined speed curve whose ordinates and abscissa: arefunctions, respectively, of sfleed .of the vehicle and the d stance trave ed under said conditions. Systems producing this result are well known to those versed in the railway signalling art. The known systems comprise a vehicle ment havin a member, or medium,

is adapte to chan gradual] in pro rtion to the travel 0 the vehic e or to e lapse of time and a speed-responsive device, such as a centrifugal governor which coacts with said member or medium in such a way as to 1m se under caution conditions a gradually ecreasing speed limit. The

system of the resent invention, while accogilplishing thls general result, has a novel in e of operation and possesses certain important advantages 'overtems. Y

In the system of the present invention, the permissive speed .of the vehicle is established by means of a medium which changes in condition or position at a. predetermined rate, the rate of change determining the permissive speed. rating. with the medium which establish; the permissive speed is a second medium which chan at a rate proportional tov the travel of t e vethe f known syshicle, and this medium coacts with the first medium in such a way that whenever the rate of change of the second medium exceeds that of the first medium'vehicle controlling mechanism will be brou ht into operation, either to retard thepve icleor to give a caution indication or. both. The .in--

n, in the District of- .COlumbia, have invented certain new and a railway vehivention thus device in w ich the permissive sfeed is established by the rate of chan e o a suitable medium, which rate is apted to be selected in ditions.

Having stated in a general wa nature and 'object of my invention now describe s ifically a system embody: ing the invention by reference to the ac companying drawings, whereof h Fig. 1 is a diagrammatic view illustratprovides a variablespeed limit accordance with any given con-- the I will ing a railroad and a vehicle travelling thereon having an equipment embodying the present inventio Fig. 2 is a longitudinal sectional view through certain controlling mechanism carried by the vehicle.

Fig. 3 is a similar view illustrating a modification.

' Referring to Fig. 1, there is illustrated a into block sections, the rails ofeach section forming a 'ortion of a closed track circuit which includes a batte to the rails at the exit end 0 the block and a relay 11 connected to the rails .at the entrance end. A ramp rail 12 is .located adjacent'to the entrance of each block and is connected to the track rail throu h a batte and through. front contacts o the tree relays connected to the .two blocks immediately in advance. It will be understood, therefore, that when a vehicle occupies either of the two blocks immediately in advance of a ramp rail the latter will be disconnected from its batter while, on the other hand, if the two bloc immediately in advance of a ram? rail are clear, the

ram will be ener 'z The vehicleequipment includes a shoe 13 adapted to contact the ramp rails and a rela- 14 which has a stickcircuit which inclu es a switch 15 operated by .shoe When shoe 13 passes onto a ramp rail,

10 connected I Figs. 4 and 5 are'detail views illustrating certain parts of the vehicle carried mechaswitch 15'i's opened, thus breaking the stick circuit of rela' 14, and if the ramp rail is at this time batte b reason of another vehicle being in one o vance, or from other cause, relay 14 willbe deenergized and drop its armature, and

e two blocks immediately in ad-.

isconnected from its waysidedisk 26. Disk 27 iskey cannot again pickup until an energized ramp is engaged b shoe 13. If, on the other hand, the two blocks immediately in advance are clear, the ramp will be connected' to its wayside battery and current will flow therefrom through relay 14, holding it u until the stick clrcuit thereof has been re ormed by the passing .of the shoe from ramp 12 and the closin of switch 15. The system thus far described is. familiar to those versed in this art. It forms no part of the present invention and is illustrated merely to show one way of controlling the devices embodying the invention, which will now be described. Permanently cared to a non-driven wheel of the vehicle in any suitable way is a worm shaft 16 which drives a worm wheel 17 journaled' in any suitable manner on the vehicle. The-worm shaft 16 and worm wheel 17 are permanently in engagement so that the worm wheel will rotate at all times while the vehicle is in motion in exact proportion to the rate of travel of the vehicle. Referring more particularly to Fi 4, which shows a side view of worm whee 17, it will be observed that the worm wheel is provided with an insulated slot 18 which has yieldingly mounted near one end thereof a contact 19, which is connected to an insulated ring 20 on the shaft of worm wheel 17. A brush 21 in the brake controlling circuit contacts ring 20. Extending into the slot 18 is a pin 22 which is fixed to a disk- 23, which, in turn, is fixed to a shaft 24. Rotatable on shaft 24 is a spur gear 25 which is frictionally engage by a disk 26. vDisk 26 is ieldingly pressed against gear 25 by a numr of coil s rings w ich surround pins fixed to a disk 2 and passig thro h holes in to she 24.- Gear 25 is driven through a suitable reducing qnently the worm wheel 1 is gearing from an electric motor 28, the reducmg gearm shown consisting of a worm 29 driven by t e armature of the motor, a worm wheel 30, and a small spur gear 31 meshing with r 25. The motor circuit is normally 010 through a front contact 32 of relay 14, the circult including a battery 33. The motor, therefore, is normally operating and at maximum speed. The brake contro circuit includes battery 33, brush 21, ring 20, contact 19, pin 22, a brush 34 electricallyconnected to pm 22, and any suitable electrically controlled brake governing mechamsm 36. Normally, therefore, this brake controlhng circuit will be closed as long as the worm wheel 17 does not rotate faster than disk 23. Since normallythe motor 28 rotates at maximum speed, thedisk 28 will rotate at maximum and com permitted to rotate at a maximum ;,w1thont .overrunning disk 23 and ca separation of pin 22 from contact 19, which would cause mum speed limit which an application of the brakes. This mechanism, therefore, normall im a max:-

0 ve icle may not exceed without application of the brakes.

When the vehicle approaches a hazard, or

under caution conditions, it is desired to ima duall decreasin speed limit, so ill the t ehicle will necess ar' y be bro ht to a minimum safe speed before the haze is reached. In the specific embodiment of the invention illustrated, this is accomplished by the following mechanism: A mutilated gear wheel 36 is journaled in a oke 37 connected tothe plunger of a solenoid 38. When the solenoid *is deenergized the gear 36 is ada ted to drop into engagement with a gear 39 ed on shaft 24. The solenoid is normally energized by a circuit including battery 33 and a front contact 40 of relay 14, so that the gear 36 is normally held up out of en agement. with gear 39. Gear 36 0 rates a exible shaft 41 which is connec to rotate an arm 42 over a circular series of contacts 43 which are connected to difierent points of a resistance 44. Gear 36 is biased y a wei ht 45, or othersuitable means, to assume t e normal position shown in Fig. 1. In this position the arm 42 makes contact with a terminal contact 46 which is connected to' the other terminal contact 47 of the rheostat.

The 0 ration of the mechanism thus far descri may be briefly set forth as follows: As already stated, under normal clear conditions, the motor 28 is operating at maximum d, as the rheostat 44 under these conditions is shunted by front contact 32. Now when the vehicle approaches the I entrance to a block, the block in advance of which is occupied, relay 14 will dro its contacts,o ning the normal circuit 0 the motor an opening the circuit of solenoid 38. Theo ofthe normal motor circuit inserts e rheostat 43 into said circuit, and as the arm 42 is now engaging contact 46, the motor circuit will inc u e e maximum resistance of the rheostat. Hence the speed of v before the brake controlling circuit is broken b separation of thew contacts, the speed of emotor is brought up to maximum by the am moving from contact 46 ontocontact48 ,thuscuttmgouttheresist-" ance in the motor circuit.- It will be observed that the gear 36 is brought into enggemsntyith 39 simultaneously with e breaking the normal motor circuit, and as it requirm only a slight movement of 36tocausearm42tomovefromcon- 46 toeontact 48, it will be understood that the up of motor-'28 will be only cause an application of the brakes, even if momentary and not of sufiicient duration to the vehicle is travelling at maximum speed.

If, however, under these conditions there should be anythi wrong with the mechanism reventing t e operation of gear 36, p 7 would not move from contact 46 and the vehicle would quickly have im upon it a minimum speed imit. is device, therefore insures. the initialv operation of gear 36. The continued movement of the vehicle after receiving a caution indication will cause thearm 42 to move over the contacts of rheostat and gradually increase the the'disk 23 to be' driven at a disk 23 without causing Under certain conditions it may happen that the slowing down of motor 28 consequent to the opening of its high speed circuit by the dropping of relay 14 will cause the brake controlling circuit to be' opened prior to the speeding up of the motor by. the movementof arm 42 on to contact 48. This might occur if at the time relay 14 is deenergized the vehicle is travelling at such a speed that the contact 19 is just on the point of leaving pin 22.v Under such conditions, any slowing up of disk 23 whatever would cause the pin to leave the contact and open the brake controlli circuit. To take care of this critical con ition, therefore, I prefer to make the brake controlling mechanism 35 sufliciently slow act to insure that it will not apply the. brakes fore the brake controlling circuit has been reformed by the speeding up of the motor consequent to the engagement of arm 42 with contact 48, al-

though the same result might be'" accomphshed in other ways ustas well, as, for in stance by causing t a contact 32 to be opened an instant after contact 40.

Figs, 3 and 5 illustrate a slight modification of the control mechanism. The construction shownby t ese figures is the same as that described 'above' except that a dificrential mechanism is substituted for the pin and slot construction. In the modification the shaft to which wormwheel 17 is fixed drives one of the large gears of a differential the other; lar of said difierential bding to 5W3;

.a frame 54 whichis rotatable on shaft M these the vehicle driven at the minimum the motor; and w employed, this may be done very simply by ireyed The planetary gears 53 o t e difierentialare journaled in tions, but by constructingthisi device sothat and the shaft ofworm wheel 1 7. Frame 54.

carries an arm 55 which is adapted to contact relatively fixed stops 56 and 57, whereby the movement of tionis limited. Arm 55 is adapted to operate a switch 58 which is in the brake controlling circuit. In this modification the gears 50 and 52 are rotatedin opposite directions bythe'vehicle andmotor respectively. When rs rotate with the same angular vethe frame 54 remains stationary.

50 should rotate faster than the motor riven gear 52, the frame 54 will move in a clock-wise direction, looking at Fi 5, thus *causingilllile switch 58 to open. movement of e 54 in a clockwise direction is limited by sto 57. to a small amount, so"..that when t e vehicle locity slows down, so as to cause gear 50 to rotate slightly slower than gear 52, frame 54 will.

move in a counter-clockwise direction immediately reforming the brake controlling circuit. It will be understood that, when the frame-is stopped by either stop 56 or ates 57, the gear 50 may continue to rotate an the motor 28 may continue tooperate by rea- I son of the frictional connection between gear 25 andshaft 24.

The system described has several advantages over the known systems for reducing the same general result. In the. rst place the present system is extremely flexible with regard 'to' the s ed to impose, in that the. speed limit may be changed by simply changing the speed of ere an electric motor is frame 54 in either direc-' d limits which it is adaptioo changing the im ance in the motor circuit.

I111 the second p ed be 0 s" a' rmanent y engag gearing Fwein thd wheels of the vehicle and the device nsive to the vehicle travel, making it possi le to employ an extremely strong aring permanently connecting these parts. I: the systems heretofore known, the memthe present system ember responsive to the vehicle travel is of necessit normally held out of action and is adapted to be thrown into connection with the vehicle wheels b a clutch, movable gear wheel or the like. f the clutch mechanism should fail, the system would fail and the failure would be on the side of danger. In the system of the present invention, on the otherhand, there are no movable parts which must be operated in order to bring the vehicle responsive device into action; the ve-' hicle responsive deviceis permanently geared gearing which .may be made. practically indestructible.

to the vehicle wheels by a The resent invention in the form illustra does employ a device which must be thrown into operation in order tobring. the limit down from a maximum to a prestar-mined under caution condi-v it will have a normal biased position in which it a minimum speed limit and by requiring said device to be operated away from this sition as a conditlon precedent to the esta lishment of a high s 'limit,

assurance is ,given thatfthe device will be set in operation before the vehicle can pro-- I pgsition it will permit the vehicle to roceed.

other words, if the centrifuga device should fail, the vehicle could proceed at any speed. In the system of the present inventlon, on the other hand, the device which cooperates with the vehicle driven element to control the vehicle is a time driven device, and failure of this device will cause an immediate application of the brakes.

I do not intend to limit my invention to the embodiments thereof described above, as the principle of the invention can be employed in widely difiering mechanisms and it would be an easy matter to devise several such mechanisms substantially diflerent from the mechanisms described above.

I claim:

1. Railway vehicle controlling mechanism,

comprising a medium controlled by the vehicle and chan ing adually in pro rtion to the travel t ereofi a time contro ed medium changing gradually in accordance with the lapse of time, means overned by traflic conditions and controlled y-the vehicle for gradually varying the rate of change of said time controlled medium from a maximum 'hiclgand changing gradually in to a minimum during the travel of the vehicle through a predetermined distance, and means for train contro ed medium changes at a greater rate than said time controlled medium.

2. Railway vehicle controlling mechanism, comprising a medium controlled by the vehicle and changing adually in pro rtion to the travel thereo a time contro ed medium changing gradually in accordance with the lapse of time, means prevent said time controlled "medium from changing at a greater rate than said train controlled medium, means verned by trafiic conditions and controlled oy the vehicle for gradually varying the rate of change of said time controlled medium from a maximum to a minimum during the travel of the vehicle through a predetermined distance, and means for 'vmg an indication when said train contro ed medium changes at a greater rate than said time controlled medium.

3. Railway vehicle controllin mechanism a medium controll by the veroportion travel thereof, a secon medium the ving an indication when said nism, comprisin comprising a member driven in to the travel of the vehicle, a mem r driven changing in accordance with the lapse of time, a third medium governed by the difference between the rates of change of said first and second mediums, means overned by traflic conditions and controlle by the vehicle for raduall varying the rate of change of said secon medium from a maximum during the travel of the vehicle through a predetermined distance, and vehicle controlling mechanism governed by said third medium.

4. Railway vehicle controlling mechanism, comprising a medium changing proportionately to the travel'of the vehicle, a time controlled medium changing gradually in accordance with the lapse of time, means preventing said time controlled medium from changing at a ter rate than said vehicle controlled In ium, means for varying the rate of change of said time controlled medium, and vehicle governin means actuated when said traincontro ed medium changes at a greater rate than said time controlled medium.

5. Railway vehicle controlling mechanism, comprising a medium changin proportionately to the travel of the vehlcle, a I

time controlled medium changing gradually in accordance with the lapse of time, means preventing said time controlled medium from changin at a reater rate than said vehicle contro led me ium, means governed by trafiic conditions and controlled by the vehicle for gradually varying the rate of change of said time controlled medium from a maximum to a minimum during the travel of the vehicle through a predetermined distance, and vehicle retarding mechanism actuated when said vehicle controlled medium changes at a greater rate than said time controlled medium.

6'. Automatic vehicle-controlling mechaa member geared to a wheel of the vehicle, a motor on the vehicle operating independently thereof, a member driven by said motor, means for varyin the speed of the motor, and vehicle contro ling mechanism governedzby said members and actuated to retard the vehicle when the rate of movement of the first named member exceeds that of the second named member.

7. Automatic vehicle controlling mechanism, comprising a member permanently geared to a whee f the vehicle, a motor on the vehicle operating independently thereof, a member driven by said motor, :neans overned by traflic conditions and actuate by the vehicle for varying the speed of said motor, and means for giving an indication when the rate of movement of the first named member exceeds that of the second named member.

8. Railway vehicle controlling mechanism, roportlon independently of the vehicle, a connection between said members adapted to prevent the second named member from moving faster than the first named member, means governed by trafiic conditions and controlled y the vehicle for gradually changing the rate of movement of the second named member from a maximum to a minimum during the travel of the vehicle through a predetermined distance, and means governed by said members and actuated to retard the vehicle when the rate of movement of the first named member exceeds that of the second named member.

9. Railway vehicle controlling mechanism, comprising a member permanently geared to wheel of the vehicle, a' motor operating independently of the vehicle, a second member, a driving connection between said motor and second member permitting independent movements of the latter, a connectlon between said members adapted to prevent the second a member from moving faster than the first member, train retarding means actuated when the first member moves mitting independent movements of thelatter, a connection between said members adapted to prevent the second member from moving faster than the first member, vehicle retarding means actuated when the first member moves faster than the second member, means controlled by traffic conditions for normally operating said motor at a maximum speed, a device for varying the speed of the motor from the maximum to a predetermined minimum, said device being normally held out of action and having a biased position in which it is adapted to cause the motor to operate at a minimum speed, means controlled by the travel of the vehicle for operatin device a ter an initial operation establishing the maximum speed of the motor and thereafter decreasing-the speed in accordance with the travel of the vehicle.

11. Railway vehicle controlling mechanism, comprising a member permanently geared to a wheel of the vehicle, an electric motor operating independently of thevehicle, a second member having a driving connection with said motor permitting restraint of said second member without varysaid device when released, said ing the speed of said motor, means preventing the speed of said second member from exceeding that of said first member, vehicle retarding means actuated when the first member moves faster thanthe second member, means controlled by traflic conditionsfor normally connecting said motor with" a sourceof energy'through a minimum impedance, a device forvarying the impedance of the motor circuit from a maximum to a predetermined minimum, said device being normally held out of action and having a biased position in which it is adapted to insert a maximum impedance in the motor circuit, and means controlled by the travel of the vehicle for operating said device when released, said device after an initial 0 eration cutting out said maximum im e ance and thereafter increasing'the impe ance in accordance with the travel of the vehicle.

12. Railway vehicle controlling mechamsm, comprising a member driven proportionately to the'travel of the vehicle, an electric motor operating independentl of the vehicle, a second member having a riving connection with said motor ermitting it to be restrained independent y thereof, means for restraining .said second member when the speed thereof exceeds that of the first member, vehicle retarding means actuated when the first member moves faster than the second member, a device controlled by trafiic conditions for varying the impedance of themotor circuit from a minimum to a predetermined maximum, said device being normally held out of action and having a biased position in which it is adapted to insert a maximum impedance in the motor circuit, and means moving in accordance with the travel of the vehicle for operating said device when released, said device after an initial operation cutting .out said maximum im edance and thereafter increasin the impe ance in accordance with the trave of the vehicle. I

13. Railway vehicle controlling mechanism, comprising a member driven proportionately to the travel of the vehicle, an electric motor operating independently of the vehicle, a second member having a driving connection with said motor permittin it to be restrained independently thereo means for restraining said second member when the speed thereof exceeds'that of the first member, vehicle retarding means actuated when the first member moves faster than the second member, a device controlled by trafiic conditions for varying the impedance of the motor circuit, and means for operating said device when released in accordance with the travelof the vehicle.

14. Railway vehicle controlling mechanism, comprising a member driven'proportionately to the travel of the vehicle, an electric motor operatingind'cpendently of the vehicle, a second member having a driving connection with said motor ermittin it to be restrained independentl y thereo means for restraining said second member when the speed thereof exceeds that of the first member, means for giving an indication when the first member moves faster than the second member, a device controlled by traflic conditions for varying the speed of the motor from a maximum to a predetermined minimum, said device bein normally held from operation, and means %or operating said device when released in accordance with the travel of the vehicle.

15. Automatic vehicle controlling mechanism, comprising a member driven proportionately to the travel of the vehicle, an electric motor operating independently of the vehicle, a second member having a driving connection with said motor permitting it to be restrained independently thereof, means for restraining said second member when the speed thereof exceeds that of the first member, means for 'ving an indication when the first mem r moves faster than the second member, and means for varying the speed of the motor.

16. Railway vehicle controlling mechanism, comprising a member driven proportionately to the travel of the vehicle, an electric motor operating independently of the vehicle, a second member having a riving connection with said motor permitting it to be restrained independently thereof, means for restraining said second member when the speed thereof exceeds that of the first member, vehicle retarding means actuated when the first member moves faster than the second member, means controlled by trafiic conditions for normally operating said motor at a maximum speed, a device for varying the speed of said motor, said device being normally held out of action and having a biased position in which it is adapted to impose a predetermined low speed on said motor, and means controlled b the travel of the vehicle for operating said device when released, said device after an initial operation increasing the motor speed and thereafter decreasing said speed in accordance with the travel of the vehicle.

17. Railway vehicle controlling mechanism, comprising a member driven proportionately to the travel of the vehicle, a motor operating independently of the vehicle, a second member having a driving connection with said motor permitting it to be re-' strained independently thereof, means for re: straining said second member when the speed thereof exceeds that of the first member, vehicle retarding means actuated when the first member moves faster than the second member, a device for varying the speed of said motor, said device being normally held out of action and having a biased position in which it is adapted to impose a predetermined low speed on said motor, and means controlled by the travel of the vehicle for operating said device when released, said device after an initial operation increasing the motor speed and thereafter decreasing said speed in accordance with the travel of the vehicle.

18. Railway vehicle controlling mechanism, comprising a member driven proportionately to the travel of the vehicle, a second member driven independently of the vehicle in accordance with the lapse of time, means preventing the second member from over-running the'first member, vehicle retarding means actuated when the first member over-runs the second member, a device for varying the speed of the second member, said device being normally held out of action and having a biased position in which it imposes a predetermined low speed on said second member, and means controlled by the travel of the vehicle for operating said device when released, said device after an initial operation increasing the speed of the second member and thereafter decreasing said 5 eed in proportion to the travel of the vehicl e.

19. Railway vehicle controlling mechanism, comprising a member driven proportionately to the travel of the vehicle, a second member driven independently of the vehicle in accordance with the lapse of time, means preventing the second member from over-running the first member, vehicle retarding means actuated when the first member over-runs the second member, a device controlled by traffic conditions for varying the speed of the second member, said device being normally held out of action, and means controlled by the travel of the vehicle for driving said device when released.

20. Railway vehicle controlling mechanism, comprising a member driven proportionately to the travel of the vehicle, a second member having a lost motion connection with said first member, time controlledtime, means governed by traflic con itions for var ing the rate of change of said time controll ed medium, and means for givin an. indication when said vehicle controlle medium changes at a greater rate than said time controlled medium.

22. Automatic vehicle controlling mechanism, comprisin a member permanently ared to a wheefof the vehicle, a motor on e vehicle operating independently thereof, a member driven by said motor, means governed b traflic conditions for varying the speed 0 said motor and means for givin an indication when the rate of movement 0 said first named member exceeds that of the second named member. I

23. Automatic vehicle controlling mechanism comprising a member driven' roportionately to the travel of the vehicle, an electric motor on the vehicle, a second member having a driving connection with said motor permitting it to be restrained independently of the speed thereof, .means for restraining said second member when the speed thereof exceeds that of the first member, means for giving an indication when the first member moves faster than the second member, and means for automatically va ing thespeed of the motor in accordance wit traflic conditions.

24. Automatic vehicle controlling mechanism comprising a member driven ropor- 'tionately to the travel of the vehicle, an .electric motor on the vehicle, a second member driven by said motor, means for giving an indication when the first member moves faster than the second member, and means for varying the speed of the motor.

EDWARD C. SASNETT. 

